I wanted to mention that I was able to continue to use the Artem XML Membership provider after I upgraded to BlogEngine.Net v1.3.  I haven't seen any problems with the membership provider or with BlogEngine.  if you haven't downloaded and upgraded to the latest version than you should really consider it.  For a complete rundown on the features you can check out Mads blog, and for an upgrade guide you can check out Al Nyveldt's blog.

Great job guys on version 1.3!